Better control your Photoshop drop shadows

I enjoy the ease by which I can create a drop shadow effect using Photoshop’s Layer Styles. But often I want to use a variety of different drop shadows. How can I change the light source so it isn’t the same for every object?

By default, Photoshop uses global lighting to make certain that every drop shadow you apply in a document is set at the same angle, as shown in Figure A. If you want to change the light source for some of the drop shadows and leave others as they are, you have to turn off the Global Light feature.